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By dariopa
Hello everyone,

I'm currently working on a project where I want to communicate between my Arduino Pro Micro 3.3V/ 8MHz ( and a GPS breakout board ( As I want to communicate via UART, I wanted to use the library SoftwareSerial. Now, it turns out that only the pins 8 and 9 on the Arduino work for this library, all other pins it doesn't work anymore. Why is that so? Are the pins 8 and 9 the only ones that support change interrupts?

Thanks in advance for your help.
By wangcheung
i believe you need to use any pins that support pin change interrupt so 8,9, 10, 14, 15, 16 for the pro micro should all work. I use 10 for a project I have using the softwareserial library (pro micro).